Vehicle driven by an internal combustion engine and provided with a liquid cooling system

ABSTRACT

A vehicle having: an internal combustion engine provided with a plurality of cylinders, at least one cylinder block, in which the cylinders are located, and at least one head, which is fixed to the cylinder block, and a liquid cooling system, comprising a hydraulic circuit, inside of which a coolant flows, which is circulated by a circulation pump. The hydraulic circuit has an initial section, which is located inside the head of the internal combustion engine, and a final section, which is obtained inside the cylinder block of the internal combustion engine. In the hydraulic circuit, the delivery of the circulation pump is directly connected to the inlet of the initial section, and the outlet of the initial section is directly connected to the inlet of the final section.

TECHNICAL FIELD

The present invention relates to a vehicle driven by an internalcombustion engine and provided with a liquid cooling system.

PRIOR ART

A vehicle driven by an internal combustion engine normally comprises aliquid cooling system, the function of which is to keep the temperatureof the internal combustion engine around an optimal value which allowsto have high combustion efficiency without threatening the integrity ofthe internal combustion engine. Furthermore, the liquid cooling systemmay have other functions, e.g. cooling the driveline lubrication oil,cooling the turbocharger lubrication oil (if present) or heating (whenrequired) the air which is introduced into the passenger compartment bythe climate control system.

The cooling system comprises a hydraulic circuit, in which a coolant(typically water based) flows; the hydraulic circuit is partiallydeveloped inside the cylinder block and the head of the internalcombustion engine (i.e. the hydraulic circuit comprises labyrinthsobtained in the cylinder block and the head of the internal combustionengine) and develops partially outside the cylinder block and the headof the internal combustion engine. In particular, outside the head ofthe internal combustion engine the hydraulic circuit crosses acirculation pump (normally driven by the crankshaft of the internalcombustion engine) and a radiator, in which the coolant releases heat tothe external environment.

In the case of a high-performance road vehicle, the internal combustionengine has a high specific power. It has been observed that frequentlyin sporty use (i.e. when the internal combustion engine must deliverhigh powers for a long time), the head temperatures of a high specificpower internal combustion engine are particularly high (i.e. the headtemperatures are frequently even significantly higher than the optimaltemperature); such a condition has evident disadvantages because it cancause an anomalous (i.e. faster) decay of the components sensitive tohigh temperature. Furthermore, it has been observed that during normalroad use, a high specific power internal combustion engine is very slowto warm up (meaning the time needed to take the coolant to the optimaltemperature) because of the low power which is delivered (which isalways a modest fraction of the nominal power). The fuel consumption ofa cold internal combustion engine is higher than that of a warm internalcombustion engine, the delivered power being equal; therefore, if thewarm-up takes longer, the greater fuel consumption caused by theinternal combustion engine being cold becomes significant (i.e. notentirely negligible).

Patent application GB2348485A describes an internal combustion enginecomprising: a plurality of cylinders housing respective pistons, acylinder block, in which the cylinders are obtained, and at least onehead, which is fixed to the cylinder block, defines the top of thecylinders and supports a distribution system. A liquid cooling system isprovided comprising a hydraulic circuit, inside which a coolant, whichis circulated by a circulation pump, flows; the hydraulic circuitcomprises an initial section which is obtained in the head of theinternal combustion engine and a final section which is obtained in thecylinder head of the internal combustion engine and is arrangedhydraulically in series and downstream of the initial section (i.e. thefinal section receives the coolant from the initial section).

DESCRIPTION OF THE INVENTION

It is the object of the present invention to provide a vehicle driven byan internal combustion engine and provided with a liquid cooling system,which is free from the drawbacks described above and which is easy andcost-effective to make at the same time.

According to the present invention, a vehicle driven by an internalcombustion engine and provided with a liquid cooling system is provided,as disclosed in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will now be described with reference to theaccompanying drawings, which show a non-limitative embodiment thereof,in which:

FIG. 1 is a diagrammatic plan view, with parts removed for clarity, of avehicle which is driven by an internal combustion engine, is providedwith a liquid cooling system, and is made in accordance with the presentinvention;

FIG. 2 is a partially exploded perspective view, with parts removed forclarity, of the internal combustion engine in FIG. 1; and

FIG. 3 is a diagrammatic view of the cooling system of the vehicle inFIG. 1.

PREFERRED EMBODIMENTS OF THE INVENTION

In FIG. 1, numeral 1 indicates as a whole a vehicle provided with twofront wheels 2 and two rear driving wheels 3 which receive torque from apowertrain system 4. The powertrain system 4 comprises an internalcombustion thermal engine 5, which is arranged in front position and isprovided with a crankshaft 6, and a transmission 7, which transfers thetorque generated by the internal combustion engine 5 towards the reardriving wheels 3. The transmission 7 comprises a propeller shaft 8,which on one end is angularly integral with the crankshaft 6 and on theother end is mechanically connected to a gearbox 9, which is arranged inrear position and transmits motion to the rear driving wheels 3 by meansof two axles shafts 10, which receive motion from a differential 11.

As diagrammatically shown in FIG. 2, the internal combustion engine 5has eight cylinders 12 (only four of which are shown in FIG. 2), whichhouse corresponding pistons 13 (only one of which is shown in FIG. 2)connected to the crankshaft 6. According to the embodiment shown in FIG.2, the internal combustion engine 5 comprises eight cylinders 12 in a“V” arrangement, i.e. the cylinders 12 are grouped into two twin rows,which are arranged at a reciprocal angle. According to a different,perfectly equivalent embodiment, the internal combustion engine 5 has astraight arrangement of the cylinders 12 and/or a number of cylinders12. The internal combustion engine 5 comprises two cylinder blocks 14(which form a single monolithic body) in which the cylinders 12 and twocorresponding heads 15 (only one of which is shown in FIG. 2) areobtained, each of which is fixed to a corresponding cylinder block 14,defines the top (i.e. the upper closure) of the corresponding cylinders12, and supports the distribution system (i.e. the intake and exhaustvalves of the corresponding cylinders 12).

As diagrammatically shown in FIG. 3, vehicle 1 comprises the liquidcooling system 16, which has the main task of cooling the internalcombustion engine 5 and the transmission 9. The cooling system 16comprises a hydraulic circuit 17 in which a coolant (typicallywater-based, i.e. consisting of water mixed with an antifreeze additive)runs and is circulated by a circulation pump 18 (also shown in FIG. 2and actuated by the crankshaft 6).

The hydraulic circuit 17 comprises a pair of initial sections 19, eachof which is obtained in a corresponding head 15 of the internalcombustion engine 5, and a pair of final sections 20, each of which isobtained in a corresponding cylinder block 14 of the internal combustionengine 5. In the hydraulic circuit 17, a delivery of the circulationpump 18 is directly connected (i.e. without the interposition of otherelements different from pipes) connected to an inlet of each initialsection 19 obtained in a corresponding head 15 of the internalcombustion engine 5; in other words, the delivery of the circulationpump 18 is directly connected with means of respective pipes (withoutthe interposition of other elements) to the inlets of the initialsections 19. The two initial sections 19 are connected to each other inparallel and in entirely symmetric manner. Furthermore, in the hydrauliccircuit 17, an outlet of each initial section 19 obtained in acorresponding head 15 of the internal combustion engine 5 is directlyconnected (i.e. without the interposition of elements other than pipes)to an inlet of each final section 20 obtained in a correspondingcylinder block 14 of the internal combustion engine 5; in this manner,the final sections 20 are arranged in series relative to the initialsections 19 and downstream of the initial sections 19 themselves. Inother words, the outlets of the sections 19 are connected directly bymeans of respective pipes (i.e. without the interposition of otherelements different from pipes) to the inlets of the final sections 20.The two final sections 20 are connected to each other in parallel and inentirely symmetric manner.

According to a preferred embodiment shown in FIG. 3, a manifold 21(which in all cases is a pipe), to which various elements are connectedas will be explained below, is interposed between the initial sections19 and the final sections 20.

The cooling system 16 comprises a heat exchanger 22, which is adapted tocool a lubricant of the internal combustion engine 5 and is crossed bythe hydraulic circuit 17. In the hydraulic circuit 17, the outlet of theinitial sections 19 obtained in the heads 15 of the internal combustionengine 5 is directly connected (i.e. without the interposition of otherelements different from pipes) to an inlet of the heat exchanger 22 sothat the heat exchanger 22 is arranged in series relative to the initialsections 19 and downstream of the initial sections 19 themselves; i.e.the inlet of the heat exchanger 22 is directly connected (i.e. withoutthe interposition of other elements different from pipes) to themanifold 21. An outlet of the heat exchanger 22 is directly connected(i.e. without the interposition of other elements different from pipes)to an intake of the circulation pump 18.

The cooling system 16 comprises a heat exchanger 23, which is coupled toan air conditioning system of vehicle 1 and is crossed by the hydrauliccircuit 17. In the hydraulic circuit 17, the outlet of the initialsections 19 obtained in the heads 15 of the internal combustion engine 5is directly connected (i.e. without the interposition of other elementsdifferent from pipes) to an inlet of the heat exchanger 23 so that theheat exchanger 23 is arranged in series to the initial sections 19 anddownstream of the initial sections 19 themselves; i.e. the inlet of theheat exchanger 23 is directly connected (i.e. without the interpositionof other elements different from pipes) to the manifold 21. An outlet ofthe heat exchanger 23 is directly connected (i.e. without theinterposition of other elements different from pipes) to an intake ofthe circulation pump 18.

The cooling system 16 comprises a high-pressure valve 24, which openswhen the pressure at its ends exceeds a predetermined threshold value;the function of the high-pressure valve 24 is to prevent the coolantpressure to increase to excessively high values. The high-pressure valve24 is of the ON/OFF type, i.e. has only two possible operativepositions: either all closed or all open. In the hydraulic circuit 17,the outlet of the initial sections 19 obtained in the heads 15 of theinternal combustion engine 5 is directly connected (i.e. without theinterposition of other elements different from pipes) to an inlet of thehigh-pressure valve 24 so that the high-pressure valve 24 is arranged inseries relative to the initial sections 19 and downstream of the initialsections 19 themselves; i.e. the inlet of the high-pressure valve 24 isdirectly connected (i.e. without the interposition of other elementsdifferent from pipes) to the manifold 21. An outlet of the high-pressurevalve 24 is directly connected (i.e. without the interposition of otherelements different from pipes) to an intake of the circulation pump 18.

It is thus apparent that the heat exchangers 22 and 23 and thehigh-pressure valve 24 are reciprocally connected in parallel.

The cooling system 16 comprises a heat exchanger 25, which is adapted tocool a lubricant of the drivetrain 7 and is crossed by the hydrauliccircuit 17. In the hydraulic circuit 17, an inlet of the heat exchanger25 is directly connected (i.e. without the interposition of otherelements different from pipes) to an intake of the circulation pump 18and the outlet of the heat exchanger 25 is directly connected (i.e.without the interposition of other elements different from pipes) to thecirculation pump 18. In other words, the heat exchanger 25 is connectedin parallel relative to the circulation pump 18.

According to a possible embodiment, the internal combustion engine 5 isturbocharged and comprises a pair of turbochargers, each of which isassociated to a corresponding cylinder row 12. In this embodiment, thecooling system 16 comprises a heat exchanger 26, which is adapted tocool a lubricant oil of the turbocharger and is crossed by the hydrauliccircuit 17 for each turbocharger. In the hydraulic circuit 17, an inletof each heat exchanger 26 is directly connected (i.e. without theinterposition of other elements different from pipes) to the intake ofthe circulation pump 18 and an outlet of each heat exchanger 26 isdirectly connected (i.e. without the interposition of other elementsdifferent from pipes) to the outlet of the initial sections 19 obtainedin the head 15 of the internal combustion engine 5. In other words, inthe hydraulic circuit 17 the inlet of each heat exchanger 26 is directlyconnected (i.e. without the interposition of other elements differentfrom pipes) to the intake of the circulation pump 18 and the outlet ofeach heat exchanger 26 is directly connected (i.e. without theinterposition of other elements different from pipes) to the manifold21.

The cooling system 16 comprises a radiator 27, which is adapted to coolthe coolant and is crossed by the hydraulic circuit 17; alternatively,the cooling system 16 may comprise two different radiators 27 connectedto each other in series one after the other. Radiator 27 is a water/airheat exchanger and in vehicle 1 is arranged generally in frontalposition to be struck by air when vehicle 1 is moving. In the hydrauliccircuit 17, an inlet of radiator 27 is directly connected (i.e. withoutthe interposition of other elements different from pipes) to one of theoutlets of the final sections 20 obtained in the cylinder blocks 14 ofthe internal combustion engine 5 and an outlet of radiator 27 isdirectly connected (i.e. without the interposition of other elementsdifferent from pipes) to the intake of the circulation pump 18.

According to a preferred embodiment shown in FIG. 3, a manifold 28 isarranged at the intake of the circulation pump 18 to which variouselements are connected. In particular, the following are connected tomanifold 28: the intake of the circulation pump 18, the intake of theheat exchangers 25 and 26, the outlet of the heat exchangers 22 and 23,the high-pressure valve 24 and the outlet of radiator 27.

According to a preferred embodiment shown in FIG. 3, the hydrauliccircuit 17 comprises an expansion tank 29 which is directly connected(i.e. without the interposition of other elements different from pipes)to manifold 28 (i.e. to the outlet of radiator 27 and to the intake ofthe circulation pump 18).

According to a preferred embodiment shown in FIG. 3, the hydrauliccircuit 17 comprises a shut-off valve 30, which is arranged in seriesrelative to the final sections 20 obtained in the cylinder blocks 14 ofthe internal combustion engine 5; in other words, the shut-off valve 30may be arranged immediately downstream of the outlets of the finalsections 20 (as shown in FIG. 3) or immediately upstream of the finalsections 20 (variant not shown). Preferably, shut-off valve 30 is of theON/OFF type, i.e. has only two possible operative positions: either allclosed or all open. The function of the shut-off valve 30 is to blockthe circulation of coolant through the final sections 20 obtained in thecylinder blocks 14 of the internal combustion engine 5; in other words,when the shut-off valve 30 is open the coolant circulates also throughthe final sections 20, while when the shut-off valve 30 is closed thecoolant does not flow through the final sections 20.

According to a preferred embodiment shown in FIG. 3, the hydrauliccircuit 17 comprises a bypass duct 31, which is arranged in parallel tothe final sections 20 obtained in the cylinder blocks 14 of the internalcombustion engine 5, and a shut-off valve 32 which is arranged along thebypass duct 31. Preferably, shut-off valve 32 is of the ON/OFF type,i.e. has only two possible operative positions: either all closed or allopen. The function of the shut-off valve 32 is to block the circulationof the coolant through the bypass pipe 31; in other words, when theshut-off valve 32 is open the coolant circulates also through the bypassduct 31, while when the shut-off valve 32 is closed the coolant does notflow through the bypass duct 31.

According to a possible embodiment, the two shut-off valves 30 and 32could also be part of the same structure, i.e. could be obtained in asingle valve body (possibly three-way).

The shut-off valves 30 and 32 are of the ON/OFF type (i.e. have only anall open position and an all closed position) and may be passive (i.e.are thermostatic valves and open/close autonomously as a function of thetemperature of the coolant) or of the active type (i.e. are controlledby an actuator driven by an electronic control unit). According to analternative embodiment (not shown), the shut-off valve 30 could be ofthe continuous type, i.e. could assume partial opening configurations toadjust the flow of coolant which circulates through the final sections20 obtained in the cylinder blocks 14 of the internal combustion engine5 more finely.

According to a possible embodiment shown in FIG. 3, the hydrauliccircuit 17 comprises a shut-off valve 33 which is arranged in seriesrelative to the heat exchanger 25. The function of the shut-off valve 33is to block the circulation of the coolant through the heat exchanger25; in other words, when the shut-off valve 33 is open the coolantcirculates also through the heat exchanger 25, while when the shut-offvalve 33 is closed the coolant does not flow through the heat exchanger25. The shut-off valve 33 is of the ON/OFF type (i.e. has only one allopen position and an all closed position) and is of the active type(i.e. is controlled by an actuator controlled by an electronic controlunit).

According to a possible embodiment shown in FIG. 3, the hydrauliccircuit 17 comprises a shut-off valve 34 which is arranged in seriesrelative to the heat exchanger 23. The function of the shut-off valve 33is to block the circulation of the coolant through the heat exchanger23; in other words, when the shut-off valve 34 is open the coolantcirculates also through the heat exchanger 23, while when the shut-offvalve 34 is closed the coolant does not flow through the heat exchanger23. The shut-off valve 34 is of the ON/OFF type (i.e. has only one allopen position and an all closed position) and is of the active type(i.e. is controlled by an actuator controlled by an electronic controlunit).

The operation of the cooling system 16 is described below.

Both shut-off valves 30 and 32 are closed when the internal combustionengine 5 is cold, i.e. when the temperature of the coolant whichcirculates through the hydraulic circuit 17 is lower in temperature thanthe optimal working temperature: in this manner, the coolant pushed bythe circulation pump 18 crosses the initial sections 19 obtained in theheads 15 of the internal combustion engine 5 and thus crosses the heatexchanger 22 (possibly, if required, also through the heat exchanger 23coupled to the climate control system) and does not pass through thefinal sections 20 obtained in the cylinder blocks 14 of the internalcombustion engine 5 nor through radiator 27.

Operating as described above, when the internal combustion engine 5 iscold the heat produced by the combustion is initially used to heat thecoolant and to heat the lubrication oil of the internal combustionengine 5 (through the heat exchanger 22). The rapid heating of thelubrication oil of the internal combustion engine 5 allows to make thelubrication oil more fluid and thus to reduce the friction inside theinternal combustion engine 5 in appreciable manner; therefore, fuelconsumption can be reduced during the step of warming up of the internalcombustion engine 5.

Operating as described above, when the internal combustion engine 5 iscold, the temperature of the cylinder blocks 14 of the internalcombustion engine 5 is relatively high (because the coolant does notcirculate through the final sections 20 of the hydraulic circuit 17).The temperature of the walls of the cylinders 12 (i.e. the temperatureof the liners of the cylinders 12) is maintained relatively high byavoiding the cooling of the cylinder blocks 14 of the internalcombustion engine 5 (obviously only during the step of warming up). Inthis manner, the friction between the cylinders 12 and the pistons 13can be reduced during the step of warming up of the internal combustionengine 5; therefore, fuel consumption during the step of warming up ofthe internal combustion engine 5 can be reduced.

The shut-off valve 30 is open and the shut-off valve 32 is closed whenthe internal combustion engine 5 is warm, i.e. when the coolant whichcirculates through the hydraulic circuit 17 has reached the optimalworking temperature. Operating as described above, when the internalcombustion engine 5 is warm, the coolant coming from the radiator (thusat lower temperature) and pumped by the circulation pump 18 is initiallyand exclusively sent to the initial sections 19 obtained in the heads 15of the internal combustion engine 5 and only later to the final sections20 obtained in the cylinder blocks 14 of the internal combustion engine5; in this manner, a greater cooling to the heads 15 of the internalcombustion engine 5 can be guaranteed thus obtaining a significantlimitation of the maximum temperatures reached by the heads 15themselves, particularly during sporty use (i.e. when the internalcombustion engine 5 must deliver high power for a long time). In otherwords, particularly in sporty use, the maximum possible cooling isguaranteed to the heads 15 of the internal combustion engine 5 to thedetriment of the cylinder blocks 14 of the internal combustion engine 5;however, in the high specific power internal combustion engine 5 and insporty use, the problems of excessively high temperatures are moreconcentrated in the heads rather than in the cylinder blocks, and thusguaranteeing the maximum possible cooling to the heads 15 of theinternal combustion engine 5 is certainly advantageous.

When the internal combustion engine 5 is warm (but at relatively lowtemperatures), an operating mode which includes keeping the shut-offvalve 30 closed and the shut-off valve 32 open could be possible(generally for a short period of time). Operating as described above,the coolant coming from the radiator (thus at lower temperature) andpumped by the circulation pump 18 is exclusively sent to the initialsections 19 obtained in the heads 15 of the internal combustion engine 5and does not circulate through the final sections 20 obtained in thecylinder blocks 14 of the internal combustion engine 5. This operatingmode allows to adequately cool the heads 15 of the internal combustionengine 5 without cooling the cylinder blocks 14 of the internalcombustion engine 5 at the same time.

The vehicle 1 described above has many advantages.

Firstly, the cooling system 16 of vehicle 1 allows to reduce thefrictions (and thus the fuel consumption and the polluting emissions) insignificant manner during the step of warming up of the internalcombustion engine 5.

Furthermore, the cooling system 16 of vehicle 1 allows to keep themaximum temperatures reached by the heads 15 of the internal combustionengine 5 within acceptable values also in sporty use.

Finally, the cooling system 16 of vehicle 1 is simple and cost-effectiveto be implemented and has small overall dimensions.

1. A vehicle comprising: an internal combustion engine comprising: aplurality of cylinders housing respective pistons, at least one cylinderblock, in which the cylinders are obtained, and at least one head, whichis fixed to the cylinder block, defines the top of the cylinders andsupports a distribution system; and a liquid cooling system comprising ahydraulic circuit, inside which a coolant flows, whose circulation iscaused by a circulation pump; wherein the hydraulic circuit comprises aninitial section, which is obtained inside the head of the internalcombustion engine, and a final section, which is obtained inside thecylinder block of the internal combustion engine; wherein, in thehydraulic circuit, a delivery of the circulation pump is directlyconnected to an inlet of the initial section obtained inside the head ofthe internal combustion engine; and wherein, in the hydraulic circuit,an outlet of the initial section obtained inside the head of theinternal combustion engine is directly connected to an inlet of thefinal section obtained inside the cylinder block of the internalcombustion engine, so that the final section is arranged in seriesrelative to the initial section and downstream of the initial section;wherein the hydraulic circuit comprises: a first shut-off valve, whichis arranged in series relative to the final section obtained inside thecylinder block of the internal combustion engine to prevent the flow ofcoolant through the final section; a bypass duct, which is free fromheat exchangers, is arranged in parallel relative to the final sectionand to the first shut-off valve arranged in series relative to the finalsection, originates at an inlet of the final section, ends at an outletof the final section, and allows the coolant to bypass the finalsection; and a second shut-off valve, which is arranged along the bypassduct.
 2. A vehicle according to claim 1, wherein: the cooling systemcomprises a first heat exchanger, which is adapted to cool a lubricantof the internal combustion engine and is crossed by the hydrauliccircuit; and in the hydraulic circuit, the outlet of the initial sectionobtained inside the head of the internal combustion engine is directlyconnected to an inlet of the first heat exchanger, so that the firstheat exchanger is arranged in series relative to the initial section anddownstream of the initial section.
 3. A vehicle according to claim 2,wherein an outlet of the first heat exchanger is directly connected toan intake of the circulation pump.
 4. A vehicle according to claim 1,wherein: the cooling system comprises a second heat exchanger, which iscoupled to an air conditioning system of the vehicle and is crossed bythe hydraulic circuit; and in the hydraulic circuit, the outlet of theinitial section obtained inside the head of the internal combustionengine is directly connected to an inlet of the second heat exchanger,so that the second heat exchanger is arranged in series relative to theinitial section and downstream of the initial section.
 5. A vehicleaccording to claim 4, wherein an outlet of the second heat exchanger isdirectly connected to an intake of the circulation pump.
 6. A vehicleaccording to claim 1, wherein: the cooling system comprises ahigh-pressure valve, which opens when the pressure at its ends exceeds apredetermined threshold value; and in the hydraulic circuit, the outletof the initial section obtained inside the head of the internalcombustion engine is directly connected to an inlet of the high-pressurevalve, so that the high-pressure valve is arranged in series relative tothe initial section and downstream of the initial section.
 7. A vehicleaccording to claim 6, wherein an outlet of the high-pressure valve isdirectly connected to an intake of the circulation pump.
 8. A vehicleaccording to claim 1, wherein: the internal combustion engine comprisesat least one turbocharger; the cooling system comprises a third heatexchanger, which is adapted to cool a lubricant of the turbocharger andis crossed by the hydraulic circuit; and in the hydraulic circuit, aninlet of the third heat exchanger is directly connected to an intake ofthe circulation pump and an outlet of the third heat exchanger isdirectly connected to the outlet of the initial section obtained insidethe head of the internal combustion engine.
 9. A vehicle according toclaim 1, wherein: it is provided a drivetrain, which transmits powerfrom the crankshaft of the internal combustion engine to driving wheelsof the vehicle; the cooling system comprises a fourth heat exchanger,which is adapted to cool a lubricant of the drivetrain and is crossed bythe hydraulic circuit; and in the hydraulic circuit, an inlet of thefourth heat exchanger is directly connected to an intake of thecirculation pump and an outlet of the fourth heat exchanger is directlyconnected to the delivery of the circulation pump.
 10. A vehicleaccording to claim 1, wherein: the cooling system comprises at least oneradiator, which is adapted to cool the coolant and is crossed by thehydraulic circuit; and in the hydraulic circuit, an inlet of theradiator is directly connected to an outlet of the final sectionobtained inside the cylinder block of the internal combustion engine andan outlet of the radiator is directly connected to an intake of thecirculation pump.
 11. A vehicle according to claim 10, wherein thehydraulic circuit comprises an expansion tank, which is directlyconnected to the outlet of the radiator, namely to the intake of thecirculation pump.